Bridge



D. H. VAN DUZER. BRIDGE No. 25,537. Patented Sept. 20, 1859.

UNITED STATES PATENT OFFICE.

DAVID H. VAN DUZER, OF SUGAR LOAF, NEW YORK.

BRIDGE.

Specification of Letters Patent No. 25,537, dated September 20, 1859;

To all whom it may concern:

Be it known that I, DAVID H. VAN DUZER, of Sugar Loaf, in the county of Orange and State of New York, have invented an Improvement in the Construction of Bridges; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings and to the letters of reference marked thereon.

Figure 1 exhibits the arch, in elevation when completed, showing the manner of applying the grips. Figs. 2, 3, and L, represent enlarged views of the arch stones, and grips in detail. a

In the construction of arched bridges the great desideratum to be attained is strength, combined with beauty and convenience; and in order to accomplish these ends I will proceed to describe the mode of constructing my bridge which may be made of either stone, wood or iron, the same principle of gripping being applicable in either instance.

The supports or abutments, A A, of my arch are built up of masonry, as is usual in most cases, the span of them being greater or less according to circumstances. The blocks or arch stones are first wrought of the usual tapering form, according to the number to be used and the span of the arch. The faces of these arch stones are made smooth and even in order to effect a perfect fitting joint when brought together.

B represents iron rods placed near the upper and lower part of the stones or near the intrados and eXtrados of the arch. Others may be placed between these as occasion requires. These rods are to sustain the arch stones and must necessarily be made of sufficient size, adapted to the strength and span of which the arch is to be made. These rods, B, have rightangular or T blocks, C, on their ends, through which pass two screw bolts, D D; these bolts being provided with nuts, a a, for tightening up the arch stones in the following order: the spring stone, E, (reference to Fig. 1), rests upon the abutment, A.

The iron rods, B, start from this stone and extend to the third stone, G, the connection of the rods being made by the screw bolts, D, placed about the center of the intermediate stone, F; these rods pass through holes formed between the third stone, G, and the fourth stone, H, and around on the inner side of the stones, (as shown clearly by Fig. 2), where they are connected with bolts in the same manner as described for the outer side. This grips together the three first blocks of the arch. The next rods, B, which form the second grips pass around on both sides of the third stone, G, and encompass the three stones, G H I, these being clamped with screw bolts as the first three stones. In this manner the whole continuous arch is gripped together and every stone throughout the arch is firmly supported by the combined strength of the iron rods, B; and these being clamped together by strong bolts, render the whole structure when finished, one of great strength and stability. I have described this arrangement as applied to arches, or bridges of stone, but the same manner of bracing can be adapted to a wooden bridge, and in this case the blocks are formed of a shape similar to those which are made of harder material, and with these I use metal plates, L, placed on the sides and ends of those blocks around which the grips pass, these serving as guard plates to prevent the grips pressing into the blocks. The grips and metal plates, L, herein above described, are also applicable to bloplks to form straight bridge without an arc What I claim as new and desire to secure by Letters Patent is I claim in combination with the blocks E, F, G, H, I, rods B, B, blocks C, C, and bolts D, D, arranged as shown, the arrangement of the plates L, all substantially as and for the purposes herein shown and described.

DAVID H. VAN DUZER.

Witnesses:

EDGAR WELLS,

AUGUSTUS A. AoKLEY. 

